Guest OS losing drive permissions

[ThatGuyNex]

I recently purchased a cheap 2TB hard drive off of Newegg, and have been trying to get a guest server OS running properly on it. I had everything working at first, by creating a custom vmdk to directly mount the hard drive, and then setting up the guest to run as a headless service. After having it up for a few days however it seems to not be starting correctly. I noticed that the host OS (Windows 7 64bit) seemed to have stolen the mount on my newly created partition, so I unmounted it but am now receiving an I/O related access denied code while the guest OS is launching.

Any help or information on what is happening would be greatly appreciated, if any other information is needed please let me know. (I tried to post images of my disk configuration and the error however the forums doesn't seem to want to let me)

Also, the reason I wanted to have the drive mounted directly was that I figured there would be some benefit for disk I/O, if this isn't the case and I should just go ahead and mount the drive regularly and create the guest drive the normal way, please let me know.

[mpack]

by creating a custom vmdk to directly mount the hard drive

Why? Why not go the obvious route of locating a VDI on the drive?

[ThatGuyNex]

I mentioned at the end of my post that I believed there would be superior Disk I/O rates from having the drive mounted directly. However I recognize that I assumed this (it just seems like the extra translation layer from reading the VDI would cause latency, although I have no idea how the technology works) and if that is incorrect please let me know so so I can just create a VDI and be done with it. I might anyways though if I can't get the vmdk working correctly.

[mpack]

Bypassing the caching service implemented by the host OS is unlikely to result in superior performance.